Empirical work on judicial and legislative politics sheds valuable light on the importance of judicial review and the ways in which constitutional limitations are most effectively maintained. Mitchell Pickerill's examination of constitutional deliberation in Congress in the latter half of the twentieth century helps us understand the limited policy impact of the Supreme Court's constitutional rulings, which in turn begins to explain the political sustainability of the power of judicial review. It also suggests the ways in which the judiciary and the legislature can complement one another in recognizing, debating, and implementing constitutional values and commitments, while cautioning us against overly optimistic conclusions about the possibilities of "legislative constitutionalism."